Bowel Obstruction Risks Seen With Newer Rotavirus VaccinesJan 16, 2014
Two large United States-based research studies reveal a tie to an increased risk of a pediatric bowel obstruction, known as intussusception, following rotavirus vaccination.
Worries about the risk of intussusception with the rotavirus vaccine go back as far as 1999 when a tetravalent rotavirus vaccine was withdrawn following its ties to an increase of one to two additional cases per 10,000 infants vaccinated, according to Family Practice News. Clinical trials now reveal that newer pentavalent and monovalent vaccines introduced in 2006 and 2008 did not reveal the increased risk; however, newer studies from Australia, Mexico, and Brazil show an increased risk with the newer vaccines
In other words, explained HealthDay News, the intussusception risk, although decreased, was still increased, even after use of the new rotavirus vaccine, according to two studies that were both published on January 14th in the New England Journal of Medicine.
One study provides evidence of a statistically significant increase risk of intussusception associated with use of Merck’s pentavalent vaccine, RV5 (RotaTeq). In that research, Katherine Yih, Ph.D., of Harvard Medical School and the Harvard Pilgrim Health Care Institute, Boston, and associates, reviewed data from more than 1.2 million RV5 doses. The U.S. Food and Drug Administration (FDA) sponsored the research; data were derived from health plans included in the FDA’s Mini-Sentinel surveillance program, according to Family Practice News.
In the other study, the researchers reviewed data from 207,955 doses of the monovalent vaccine. The team identified intussusception cases recorded within seven days following a first or second dose. The team was led by Eric Weintraub, of the U.S. Centers for Disease Control and Prevention (CDC), and discovered 5.3 additional cases more than what was clinically expected when looking at 100,000 infants vaccinated with two doses, Family Practice Medicine reported. Data was derived from the CDC’s Vaccine Safety Datalink surveillance program, which involves data collection from health care plans that are different from those utilized in the FDA’s program.
"We observed a significant increase in the rate of intussusception after vaccination, a risk that must be weighed against the benefits of preventing rotavirus-associated illness," Weintraub and colleagues write, according to HealthDay News.
Intussusception is a serious disorder in which a portion of the intestine moves into an adjacent area of intestine, a so-called "telescoping" that may block food or fluid from passing and may also cut off the blood supply to the affected portion of the intestine. Intussusception may cause bowel perforation, infection, and bowel tissue death, according to the Mayo Clinic. Symptoms include:
- Sudden, loud crying caused by abdominal pain.
- The baby drawing his/her knees into the chest due to pain
- Stool mixed with blood and mucus ("currant jelly" stool)
- Abdominal lump